Recently, liquid crystal displays have been frequently used as display devices of computers, word processors, and small televisions. In particular, a STN liquid crystal display type has lately been put to practical use, and white STN displays and color STN displays have been noticed.
However, a liquid crystal display is readily colored to have a blue or yellow color due to a correlation of a birefringence index of a liquid crystal cell with visible rays. In the liquid crystal displays of the white STN displays and the color STN displays, coloration of the liquid crystal cell due to retardation may be reduced by adding a retardation film having a predetermined retardation to a substrate surface of the liquid crystal cell.
Stretched TAC (triacetyl cellulose) or cycloolefin polymer (COP) (for example, ZEONOR manufactured by ZEON Corp. and ARTON manufactured by JSR Corp.) has been used as the retardation film. For example, Japanese Patent Application Publication Nos. 2-191904 and 2-42406 discloses longitudinal and uniaxial stretching or transverse and uniaxial stretching of thermosetting resin films.
Meanwhile, among current liquid crystal displays that are suggested to improve a wide viewing angle, an in-plane switching liquid crystal display (IPS-LCD) includes liquid crystal molecules that are uniformly aligned almost parallel to a substrate surface in a non-operation state. Therefore, in the in-plane switching liquid crystal display, light is not affected by a polarizing plate and thus penetrates a liquid crystal layer without any changing. Thus, alignment of the polarizing plates on the upper and the lower surfaces of the substrate can give almost perfect darkness in a non-operation state. In the in-plane switching liquid crystal display, an optical compensation film is used to improve a viewing angle characteristic.